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OverTheGeicoE writes "CNET has a story on DHS' whole car X-ray scanners and their potential cancer risks. The story focuses on the Z Portal scanner, which appears to be a stationary version of the older Z Backscatter Vans. The story provides interesting pictures of the device and the images it produces, but it also raises important questions about the devices' cancer risks. The average energy of the X-ray beam used is three times that used in a CT scan, which could be big trouble for vehicle passengers and drivers should a vehicle stop in mid-scan. Some studies show the risk for cancer from CT scans can be quite high. Worse still, the DHS estimates of the Z Portal's radiation dosage are likely to be several orders of magnitude too low. 'Society will pay a huge price in cancer because of this,' according to one scientist."

The TSA should be abolished. This is getting ridiculous. I think their new plan is that if the "terrorists" have cancer they will be too weak to be a threat and the public will be too sick to be a nuisance as well. I'm slowly caring less and less about the TSA grunts, but why are they not required to wear radiation monitors for their own protection? The idiots in charge are not getting exposed to any of this, nor are they using know best practices for dealing with radiation.

The workers will get a pretty medal (designed in USA made in... ) and expect to see a term like "national sacrifice zones" dusted off as a sound bite.

The workers who have to be around these souped up xray machines for a full shift five days a week will probably get bad simultaneous cases of several varieties of cancer much sooner than even the most frequent traveler going through it. Then the government will be on the hook for huge lawsuits and removing the machines. The trick is to avoid being said frequent traveler until then.

Getting? It was ridiculous eight years ago. At this point, they've crossed the line into gross criminal negligence, reckless endangerment, and willful malfeasance. They should not merely be abolished. They, along with everyone who voted to create them, should be sent to prison with very, very long terms to set an example for anyone who might contemplate usurping the Constitution of this great nation in the future.

Throwing them out on the street with no jobs is way, way too good for these unAmerican traitors.

So you think they're dumb enough to hand the EFF grounds for a permanent injunction against their entire operation on a silver platter? The last thing they want to do is actually deny a vocal opponent of the TSA access to a flight, as that would give that person clear standing to sue them for all they're worth.

If they don't start again soon, they're liable to have a rude awakening. The fundamental social contract between the public and governments is built on mutual respect for the law. If the government ceases to respect the law, it's only a matter of time before the general public starts to imitate them. Down this path lies chaos.

1. What is an 'essential task'? Travel for work? That vacation I planned and booked a year ago?2. Where have you been? People stopped travelling in droves after 9/11. You recall what happened? We bailed out the airlines.

I share the sentiment, but its an oligolpoly at best. There are no alternatives to air travel.

Strikes don't work well against government requirements--since their budget comes from taxes, going on strike isn't going to cause them any hardship whatsoever, like it would if you tried to boycott a store.

The states can get in on this too. New Hampshire has a proposal for a new state law to record abuses by the TSA. Here's a snippet of HB0628:

"VII.(a) In order to assist in the accuracy of records created by law enforcement officers in paragraph III, all citizens being searched shall be afforded their rights under the First Amendment to the Constitution for the United States of America and under Part 1, Article 22 of the New Hampshire Constitution to record, or designated a person to record, using any type of audio and video recording device, or a device that records just audio or just video, all interactions with an agent described in paragraph I, even in the presence of a law enforcement officer, without exception."

Paragraph I specifies the TSA by name.

Followed by:

"(c) If a law enforcement officer does not enforce the provisions of this chapter or makes it difficult for a citizen to exercise his or her rights as specified in this section, the law enforcement officer may be guilty of official oppression pursuant to RSA 643:1."

But look at the health benefits if it stops people smoking weed. A car containing 10 kilos of weed contains nearly 8 kilos of weed, meaning that not only will someone go to jail for possessing 5 kilos of weed, but also the people the dealer would have supplied will be unable to obtain this dangerous drug and will perhaps instead turn to safe, legal drugs such as alcohol or tobacco.

"A car containing 10 kilos of weed contains nearly 8 kilos of weed, meaning that not only will someone go to jail for possessing 5 kilos of weed

What in hell have you been smoking?

The fail hurts.

It's a joke that the dealer had 10kg of weed, then the cops who pulled him over skimmed off 2kg (leaving 8kg). When that was delivered to the evidence lockup, the cops running that skimmed another 3kg off (leaving 5kg) which is used as evidence. The skimmed weed is then used by the cops or dealt out on the street (cops who deal primarily with drugs and cash tend to annoyingly crooked [youtube.com]).

Not only that but regular medical X-rays already have a history of accidental radiation poisoning, poisoning several hundreds of patients over several weeks (until the cause was found because the radiation poisoning was a) localized and b) easily traced because everyone had access to decent health care and knew they were scanned at some point) because a single variable was off in a program or badly set by a technician.

A single x-ray machine can do maybe 40 people a day given a 24 hour cycle. This thing will probably do 40 people every 15 minutes and has a much higher dosage by default. One or more of these things will not only kill people but it will also kill the workers and the cause won't be as easily found because cases will appear seemingly independently all over the world and in 3rd world countries (such as Mexico or people traveling internationally) so cases won't be as easily linked, people won't know they've been scanned by these things and many will die before the one is found out and then they'll only claim 1 faulty machine, implement some 'safeguards' and make empty promises but continue doing it until the next machine fails.

There's a reason why the X-ray technicians usually leave the room when X-rays are being taken. Just being in the same room ensures that you'll get at least some exposure. The new digital equipment is better than the older ones were, but you're still talking about additional radiation.

"One of the studies, which examined more than 1,000 adult patients at four hospitals, projected that the dose of radiation received in a single heart scan at age 40 would later result in cancer in 1 in 270 women and 1 in 600 men.

Risks were lower for those who received a head CT scan: 1 in 8,100 women and 1 in 11,080 men would likely develop cancer from the radiation, the study said."

These numbers don't have a direct translation for "Z Portal" cancer risk, but they're surprisingly high. Hopefully we get some very robust studies to examine the effects of the DHS scans in the near future. I guess it's too much to hope that the Department of Homeland Sarcoma would stop using the scanners until public and peer reviewed science exists to prove their safety.

"One of the studies, which examined more than 1,000 adult patients at four hospitals, projected that the dose of radiation received in a single heart scan at age 40 would later result in cancer in 1 in 270 women and 1 in 600 men.

To be fair, heart scans are the high mark for radiation dosage. Since you need to look at how the heart actually moves/cycles it take much longer to image compared to other parts of the body. There are also many different CT scanners. Some of the high slice scanners reduce the dosage considerably. The Toshiba and Philips 320/256 slice scanners can image the heart in a single rotation rather than continual helical rotations. There are also several new algorithms that use lower dosages with a worse s/n ratio then clean it up in post processing. Regardless, I don't expect DHS/TSA to concern themselves with proper radiation procedures, nor the same scrutiny towards calibration as medical devices.

At the same time, medical ethics permits that risk because the potential benefit is higher and accrues to the patient undergoing the risk. No such benefit exists for a DHS scan. We get all the risk but no benefit.

I think this may turn into a racket actually. Look at the 'trusted traveller program' (or whatever it's called now). For $120/year (or whatever it is) you get a special pass and you don't have to submit yourself to either the body scans, the lines or the cavity search.

Basically what will happen is first the TSA will screw up several times severely. The people will call for relief to the government who will make it become a privately owned entity and claim now "they'll have someone to hang". Then you'll be a

To be fair, none of it occurs in isolation. People don't go through life just having a a single xray.
They have ct scans, numerous dental xrays, xrays for other fractures, exposed to radar from airports, own microwaves, exposed to emr from high voltage lines, fluorescent lights, background radiation and, radiation from the sun.

So you asshats that like to point to your new additional radiation device as safe, as is in some fantasy world in operates on it's own and a person is not subject to other risks, w

The average energy of the X-ray beam used is three times that used in a CT scan

This assumes professional calibration! This should read "The average energy of the X-ray beam when calibrated by an apathetic TSA employee is a hell of a lot more than three times that used in a CT scan calibrated by a hospital technician"

For its part, Homeland Security says the dose is safe and based on commonly accepted government standards (PDF) established by the National Council on Radiation Protection and Measurement, which would permit 2,500 scans a year for each person. CBP's specifications also require the manufacturer to "perform an evaluation of the potential effect of radiation exposure on public safety on the proposed system." In addition, a CBP representative told CNET that the machines are currently only used in secondary inspections (most people go through just the primary inspection).

I think, as a good will gesture, the Director/CEO of the TSA and his family should undergo 2,500 scans a year.

The average energy of the X-ray beam used is three times that used in a CT scan

This may or may not be a misleading statement. There's inadequate context and specificity in the article. "Energy" here could refer to the total amount of ionizing radiation energy delivered to a person in the scanner, in which case these portal scanners could be considered extremely dangerous, since a typical CT is already a substantial and potentially dangerous radiation dose. Alternatively, the word "energy" may refer to the energy of the individual x-ray photons. In other words, if a typical CT uses 100keV x-rays and these scanners use 300keV. That is probably what was meant. It's clinically meaningless. Within reasonable ranges of several tens of keV to several MeV, only the total absorbed dose really matters health-wise, not the energies of the individual particles.

With that said, I still don't condone this type of intrusive inspection - even at the border.

First, I haven't read TFA but, I live 5 min form a us Canada border crossing. They have been doing this for months now. When they scan the vehicles they have the occupants exit the vehicle and stand in a "safe area" over 100 ft away from the truck doing the scanning.

I'm wondering what if you don't consent to the x-ray. Will they throw your ass in jail for not willing to cooperate? If you are a tourist from Canada, are you allowed to turn-around and not go to the states? (this will obviously complicate any future returns)

It seems people have already had problems when they turn around at the airport or refuse the other xray equipment.

I'd like to see a waiver form. Do you consent to an xray? Are you aware that these pose a cancer risk? Are you aware that these machines may not be sufficiently or professionally calibrated which may increase your risk of cancer?

I'm a Canadian. So long as these scanners are in place, I'm going to reconsider any traveling to the US.

This policy is in place to catch money/drug/weapon smugglers and presumably terrorists. None of this will halt.

Based on my experience with DHS checkpoints (at this time, things will undoubtedly get worse as time progresses), as long as you do not raise your voice or object, they will search your vehicle and all of your persons, including warrant checks for all. If they find anything like a gun or a small bag of drugs, they will run all of the checks and contact the local highway patrol to do the actual booking. This "keeps America safe" while generating plenty of revenue for the states.

If you do raise your voice or object, they will charge you with a blanket offense like "insulting a federal officer" or "terrorist threats." Don't laugh - an unarmed transgender [youtube.com] with both arms in the air was tazed in the crotch by the BLM pigs. S/he was later charged with "terrorist threats."

Anyway, if you're clean, you will be released eventually, put on a watch-list, and harassed everywhere you go. God bless America.

Do these plastic anti-scanning bags which are used to protect electronic components and hard drives from powerful x-raying machines not work against these x-raying machines in the U.S.?

I would imagine that it depends on the power of the x-ray. From what I understand the machines designed to inspect baggage are quite powerful - it will fog film even in a protective bag (though these bags are effective against scanners designed to be used around people).

Also, I imagine that a bunch of opaque objects in a scan that appear suspicious would trigger a manual search.

This story is crazy. I don't have any objection to using x-rays on unoccupied vehicles, but doing a CT-scan with people inside is

The problem here is that these machines (and the ones like them at the airports) were never about public nor personal safety. They were always about creating the appearance that we are safer and making a few people with ties to the TSA quite wealthy. Until we actually fix the military-industrial-complex-like problems that plague our government at almost every level, we will increasingly have to deal with these stupid issues.

The article specified X-rays or gamma rays. I hate the DHS more than anybody else here, because I have to drive through their checkpoints on a fairly regular basis, but I would hope that they would at least make everybody get out of the car and at a safe distance away from the machine while the scan is performed. They're looking for large amounts of money, dope, guns, or explosives; things that would not be carried on a person.

Also, as the guy below stated, freedom-loving Americans (and foreigners with business in the 'States) need to be more proactive at expressing their displeasure of the DHS.

When I was in the 4th grade, our social studies teacher explained that America was better than "Russia" because of a number of things they did that we didn't do. Every day, we are doing more and more of those things right here in America.

Harassing TSA agents, DHS inspectors, or even the police is counter-productive. While there are "bad apples" who abuse their authority, most are just regular people trying to do a job which means constantly dealing with pissed off people. After a stint in a support and warranty call center, I can really sympathize with them -- there's nothing THEY can do about it, same as I couldn't wave a magic wand and make a warranty valid a few weeks after it expired, no matter HOW much a customer yelled at me.

Stick to hounding the government and the three letter agencies that make the DECISIONS to deploy these people, but let them do their job until their jobs are eliminated.

Harassing TSA agents, DHS inspectors, or even the police is counter-productive. While there are "bad apples" who abuse their authority, most are just regular people trying to do a job which means constantly dealing with pissed off people. After a stint in a support and warranty call center, I can really sympathize with them -- there's nothing THEY can do about it, same as I couldn't wave a magic wand and make a warranty valid a few weeks after it expired, no matter HOW much a customer yelled at me.

Stick to hounding the government and the three letter agencies that make the DECISIONS to deploy these people, but let them do their job until their jobs are eliminated.

You weren't actively harming people. You were not acting against their Constitutional rights. You weren't acting against their human rights. The TSA agents may very well be actively harming people. Just following orders has been determined NOT to be a valid defense even for a draftee in the military. It certainly isn't for a civilian job with the TSA.

Gamma radiation I could see, but X-Rays have a GREAT deal of difficulty penetrating metal.

There is no real distinction between X-rays and Gamma rays in terms of their properties. They are named based on how they were produced and their application. Create them by accelerating electrons into a metal target in a hospital and you call them X-rays. Create them in nuclear or particle decays and they are called gamma rays. In fact if you create them by smashing high energy electrons into a metal target in a particle physics lab we'll call them gamma rays as well.

As for penetrating metal we make calorimeters designed to measure photon energies which consist of plates of dense metal - like lead, depleted uranium etc. As the photon penetrates these metal sheets it makes a shower of particles and we count the particles in the gaps between the metal plates. Such detectors are usually metres thick for GeV photon energies (probably at least 1,000 times higher than what these machines use - I hope!). But the point should be clear - give a photon enough energy and it penetrates lead and depleted uranium - so the thin sheet metal in a car is not an issue. However I'd not want to be driving a car which is being subjected to that.

So... all those X-rays I've seen being taken of welds on pressure vessels and structural nodes... are just fakes. Well, that makes me feels so much safer as I watch rust-cicles getting longer on the support frames for the drilling platform.

Trust people like Fred to be lying about the NDT work he gets paid for. He must just bash up the pictures in Photoshop. All the barrier chains, warning tannoys and other palaver is just smoke and mirrors.

Same AC. Just wanted to clarify due to the present "Score:4, Funny", that I'm completely serious. They contacted me in 2006 for this project, since I have both a programming and physics background. Once I learned more, I told them to stuff it.

These xrays are much more powerful (intensity and energy) than medical xrays.

I know someone that walked in front of one of these running machines a few decades ago (by accident, of course). He sufferred accute radiation poisoning that required almost 2 weeks to recover. Day after exposure, he almost could not walk.

Still, there is SOME kind of scanner technology that they DO use to inspect the cargo of 18-wheelers without emptying out the load. But it's NOT X-Rays.

Keep repeating after me. Ignorance is bliss. Ignorance is bliss. Ignorance is BLISS!

No risk, such as radiation, is too great in the face of security. Consider this kind of system [wikipedia.org]. It politely asks people to move away. Side effects may include burns, cancer, and death.

I love our country. I'd love it more if they'd stop trying to kill me in the name of security. In the future, this whole period will be looked at with great disdain The question will be, how many will survive to tell the tales? The cancer clusters from those who operated the equipment and f

These xrays are much more powerful (intensity and energy) than medical xrays.

Which is the problem ( well, the health problem.. the fact we are doing it at all is another issue ) I guess this ensures that i will never be traveling abroad. While I'm already middle aged, i don't want to push my luck and shorten my lifespan, or destroy my quality of life as i get older..

Yep, I interviewed at a company back in the 90s that made equipment to do X-ray inspection of steel welds. We're talking about things like 6-inch thick steel plates (and thicker), welded together; they would X-ray the joints to make sure the weld quality was sufficient. X-rays penetrate steel just fine, but you need very, very powerful equipment. Using it on a human is probably a death sentence, or at the very least will cut many years off your lifespan.

You do realize that your average trailer, the kind that semis pull around, has barely any metal in it, right? I've seen in the back of hundreds of them over the years and they're actually mostly wood with a thing metal covering to protect against the rain. It's probably not any thinker than the metal in a soda can.

X-rays are absorbed by a material by interacting with the electrons around the nucleus (or with the nucleus itself). This is a statistical question - X-rays will penetrate a short distance into a material. the more dense the material or higher energy (frequency) of the X=rays, the less they will penetrate. See for examplehere [ndt-ed.org].

There is a table at the bottom of penetration depths through lead as a function of energy of the X-rays.

Funny, then, that my research focuses on the behavior of X-rays through metals. X-rays can penetrate metals, depending on the energy of the radiation used. high-energy radiation passes through almost everything, and interacts only a little with intermediate objects. Hence, it is very well possible they are using X-rays for this, but they can pretty much only use it to visualize the internal metallic structure of objects as it will pass right through people.

It is likely Gamma, and it is actually an older technology. The DDR (Stasi-run former easter Germany) used Cobalt-60 sources to screen trucks for people hiding in them. Anybody in there would have gotten a serious dosage. Sometimes the drivers got this dosage as well, as the shielding on the Cobalt was retracted to early (this was done for moving trucks). All this was done in secret.

I think, once again, it is quite clear where the DHS got its inspiration.

And yes, even X-Rays penetrate metal just fine, just crank up the intensity. Typically Gamma is used though, because it penetrates a lot better at lower intensities. On the minus-side, for Gamma you need radioactive sources, while X-Rays can just be generated with electricity.

On the plus side, gamma sources are a lot more portable and don't need electricity. It's still a pain carrying the things up ladders though becuase of all that lead required to sheild even very small sources.With a gamma source just about all you can do is open the door (I've read about filters to reduce intensity but never seen one). With an X-ray source there is a lot of control, and apparently it's a lot easier to collimate. I can't remember how thick the thickest welds and casting I saw X-rayed but i

I haven't touched it in nearly 15 years and was an engineer and not a real radiographer. While I could interpret the images I didn't ever do any unsupervised exposure calculations, so I mostly just helped out moving the gear so more could be shot in the same time window. Typically everybody on a very large area of a site (or an entire site) goes to lunch offsite while the radiography is done - or the same sort of thing for a period late at night. The idea is that everyone that isn't under direct visual supervision of someone with a clue about radiation safety is hundreds of meters away so isn't going to wander within twenty meters of the source when the door is open.Others will have more current information and more experience.

Anyway, the thing that scares the hell out of me about the TSA stuff is that no trustworthy third party has to look at it so you just have to take their word that radiation safety is even being considered at all. Their operators don't need to be trained to any sort of standard recognised by any authority anywhere so can not be trusted to safely operate the equipment. I'm not going to the USA any time soon but if I do I'm going to make sure I don't get exposed to any sort of amataur x-ray even if that means I have to get deported for refusing it.

X-Rays can penetrate metal. For example, a standard thing in car fabrication is to X-ray the welds to look for defects.

It's a matter of intensity as with all things - for example your hands look pretty opaque under normal sunlight, but if you put a torch up against them you can see the glow coming through quite clearly.

The issue here is that the intensity of X-Ray radiation you'd use to scan through a steel and aluminium car body is considerably higher then that used in a conventional medical X-Ray.

Think of the settings e.g. bike, car, van, truck, big truck, heavy engineering equipment...
Your paper work shows your flagged as having sold your home, moved cash around the world and seem to be emigrating..
A final zap good-bye

So maybe Congress can create a health-care "reform" bill so complicated no one can understand it, but filled with enough time bombs and hidden boobytraps to eventually crash the private insurance industry. Wow, that's an incredibly cynical idea. I can't believe I could think of something so sinister.

You're kidding me, right? The so-called 'Obamacare' bill that got passed was just a bailout for the healthcare insurance 'industry'. Healthcare insurance never needed a bailout. It was written by the lobbyists for the healtcare insurance industry. Do you really think they woulda written in little booby-traps to kill off the corporations that sign their paychecks? Be real.